In the field of microelectronics, processors are currently being fabricated with increasingly higher clock frequencies, ranging typically from several GHz to around 20 GHz in the case of certain prototypes. This improvement in the performance of microprocessors makes it possible to process digital information more and more quickly and hence makes it possible to solve increasingly complex algorithms in an ever shorter time.
This is why attempts are also being made to develop transceiver devices capable of transporting this digital information at increasingly high speeds in order to keep up with the processing speeds of microprocessors.
Transceiver assemblies according to the prior art include electronic devices with various architectures, the operation of which depends on the intended application. The way in which the digital information is transported, i.e. encoded and then decoded, depends on the rate at which information is to be sent and the distance over which the information must be sent. This is why many communication standards have been created in order to meet various specific needs. These standards fall into three categories.
The first category comprises “non-differential” standards, the best-known of these being:                The Low Voltage Transistor Transistor Logic (LVTTL) standard is used over a single-circuit line at a frequency below 250 MHz;        The Gunning Transceiver Logic standard uses a single-circuit line, the transistor drain of which is not connected and operates at frequencies below 200 MHz.        
Both these standards are generally used in traditional electronic circuits over relatively short interconnection distances (e.g. the GTL standard or even the external communication bus of Intel's Pentium Pro) and for moderately high bit rates. The AGTL+ standard is derived from the GTL standard and is used to transport high bit rates by means of motherboard buses.
The second category is associated with communication needs between the various elements of a single electronic unit. Where information has to be transferred between memories, significant bandwidth is required, especially for high-speed memories such as Static Random Access Memories (SRAM) and Dynamic Random Access Memories (DRAM). In such applications, one generally uses the High Speed Transceiver Logic (HSTL) standard or the Sub Series Terminated Logic (SSTL) standard which make it possible to transport digital information over very short distances at frequencies of the order of 400 MHz by means of single-circuit or differential lines.
The third category comprises differential standards for transporting very high information rates, typically at frequencies above 800 MHz over long distances, sometimes over several hundred meters, as in the case of Asynchronous Digital Subscriber Line (ADSL) networks, one can employ serial point-to-point links which operate in accordance with Low Voltage Differential Signaling (LVDS), Emitter Coupled Logic (ECL) or Current Mode Logic (CML) standards.
As is known, the LVDS standard uses CMOS-based technology which enables it to achieve a good trade-off between cost, power consumption and performance of the order of 1 Gb/s for a power of 1 mW.
As for the ECL and CML standards, these make it possible to transport information at higher bit rates, typically of the order of 2 Gb/s but with a power consumption which is markedly higher than that in the case of the LVDS standard, typically of the order of 200 mW and at greater cost because these standards use non-standard technology.
The technology employed by the LVDS standard uses small currents of the order of 3.5 mA and a differential connection to transmit information over long distances and this makes it possible to reject most of the noise which affects transmission lines because most of this noise is common mode noise and differential circuits reject an extremely high proportion of such noise. This noise rejection makes it possible to use low voltages and hence reduce power consumption.
The present invention falls in this third category of differential transceivers for long distances which also offer a high information rate, but without any of the disadvantages of the LVDS standard.
According to the LVDS standard, the transmitter output voltage swing is relatively high, of the order of 350 mV, which corresponds to the operation threshold of the gates of the receiver's input transistors. Since operation is differential, the voltage swing equals at least twice this threshold, i.e. approximately 700 mV. The current required to transport digital information, although low, remains relatively high, of the order of 3.5 mA. Consequently, the dynamic power required to generate the signals which transport the digital information is of the order of 2.1 mW, and cannot operate below a differential voltage swing of 700 mW.
In addition, bearing in mind the electrical impedance of the transmission line, the integrity of the transmitted signals cannot be guaranteed where transmission distances exceed 15 m. Moreover, this impedance prevents these electronic devices from addressing digital information from a single transmitter to a plurality of receivers because the signals are degraded when they are received.
The object of the present invention is therefore an electronic device which does not have the drawbacks of devices according to the prior art, especially excessive power consumption, a limited information transmission range and/or a high implementation cost and limits as far as the number of receivers are concerned.